Direct cytotoxicity, ADCC, recognition specificity and cytotoxic potency of γδ NKT cells against cancer cells.

(a-b) γδ NKT cells generated from GDTA/NF-iPSC#1 were used for direct cytotoxicity assay against a wide variety of cancer cell lines (a) and ADCC against Raji cells in the presence of humanized anti-CD20 antibody (b). (c) Cancer recognition specificity of γδ NKT cells was investigated by comparing direct cytotoxicity of γδ NKT cells against normal cells or non-tumorigenic cells and their malignant counterparts. The statistical significance of difference in (b) and (c) was determined by Student’s t-test (mean ± SD, n = 3, *p < 0.05, **p < 0.01, ***p < 0.001, ****p < 0.0001). (d) Cytotoxic potency of γδ NKT cells was evaluated by comparing their cytotoxicity against cancer cells with that of donor γδ T cells and donor NK cells. γδ NKT cells from three batches, donor γδ T cells and NK cells from six donors were used in cytotoxicity assay at an E:T ratio of 5. The statistical significance of difference was determined by Student’s t-test (mean ± SD, n = 3).